Аннотация:The article presents the set-theoretic models of liver failure, allowing the diagnosis of the disease forms and personalized selection of traditional and new methods of treatment. Separate types are presented in the form of 5 sets which correspond to the known clinical forms of the studied pathology: "chronic liver failure", "acute-on-chronic liver failure", "acute liver failure", "fulminant liver failure" and "drug-induced liver injury". The models allow to take into account the dynamics of transition from one form to another in the process of developing the disease with continued influence of negative factors. The proposed approach allows the difference in the clinical manifestations of the pathology, the fuzzies of the transitional disease states, specific and nonspecific signs of etiologically and pathogenetically different forms, which are the criteria for selecting similar cases to choice the most effective therapies. Personalized treatment is based on comparing a patient with a specific subset of the multiset.